There are also some great independent documentaries, and I love it when filmmakers take on the establishment, especially when it comes to important environmental issues. Here are five of my favorite documentaries that are at times frightening and funny, but always enlightening.

1. ‘GasLand’ (2010). Ever see tap water lit on fire? It’s frightening, even experienced through a movie or TV screen. Written, directed and produced by Josh Fox, this runaway hit throws a big wet blanket on Halliburton and other drillers’ notions that natural gas is America’s great hope for energy independence. Fox launches an investigation into the practice of “fracking” — hydraulic drilling for natural gas — after a company offers him big bucks for a lease on his family home in rural Pennsylvania (which happens to sit on top of one of the world’s largest reserves of natural gas).

Fox’s personal journey takes us from the Congressional hearings that exempted natural gas companies from the regulations of the Safe Drinking Water Act to kitchens across the USA where tap water contaminated with fracking fluid can be lit on fire. This movie is activism at its best, shedding light on an an issue at the forefront of American energy and environmental policies. ‘Gasland’ official site; 107 min.; HBO Documentary Films.

2. ‘Food, Inc.’ (2008). Written, directed and produced by Robert Kenner, this doc exposes the truly alarming way that food isproduced and distributed in the United States. Interviewing investigators, journalists and farmers, Kenner reveals that almost everything we eat is produced and distributed by just a few huge multinational corporations, such as Monsanto and Tyson, and that quality of nutrition is secondary to production cost and corporate profits.

The statistics, expert opinions and commentaries by whistle-blowing farmers in this film are shocking. Even worse, footage showing inhumane, unhealthy and unsanitary conditions of livestock and of food industry workers is horrific. ‘Food, Inc.’ official site; rated PG for some thematic material and disturbing images; 94 min.; Magnolia Pictures.

3. Up the Yangtze (2007).Written and directed by Yung Chang, this doc takes you cruising down China’s mightiest river to meet the people whose lives were altered by construction of Three Gorges Dam, built to harness hydro power. The dam’s construction has played ecological havoc along the historic waterway’s entire length, and the effect on the lives of countless citizens has been devastating.

Ironically, tourism swelled as the waters rose to forever engulf the famously scenic Three Gorges landscape, but at what cost? This film examines short-term economic gains versus long-term ecological loses. ‘Up the Yangtze’ official site; 93 min.; Zeitgeist Films.

4. ‘King Corn’ (2007). Two friends, one acre of corn, and the subsidized crop that drives our fast-food nation are the subject of this compelling doc. Ian Cheney and Curt Ellis, best friends from college on the East Coast, decided to move to the heartland to learn where their food comes from. With the help of friendly neighbors, genetically modified seeds, and powerful herbicides, they plant and grow a bumper crop of America’s most-productive, most-subsidized grain on one acre of Iowa soil.

But when they try to follow their pile of corn into the food system, what they find raises troubling questions about how we eat and farm. ‘King Corn’ official site; directed, written and produced by Aaron Woolf; Balcony Releasing; 88 min.; buy ‘King Corn’ on Amazon.

5. ‘Cane Toads: The Conquest’ (2010). Directed, written and produced by Mark Lewis, this comedic documentary, shot against the harsh and beautiful landscape of northern Australia, tracks the unstoppable journey of the toad across the continent. Lewis injects irreverence and humor into the story as he follows a trail of human conflict, bizarre culture and extraordinary close encounters.

‘Cane Toads: The Conquest’ is the first Australian digital 3D feature film, employing custom designed equipment that allows viewers to get up close and personal with these curious creatures like never before. The unique viewing experience is like being immersed in the world of the toad. ‘Cane Toads: The Conquest’ official site; rated PG for disturbing images, language including drug references, and brief smoking; Radio Pictures; 85 min.; not available on DVD yet.

Jane Boursaw is the founder and editor-in-chief of Reel Life With Jane. Her credits include hundreds of print and online publications, including The New York Times, People Magazine, Variety, Moviefone, TV Squad and more. Follow her on Twitter at @reellifejane.

I did not know about the last three and will check them out. I have heard great things about Bag It. I also found Blue Gold fascinating, and the idea that George W. has already purchased land above the biggest aquifer in the world, in South America. Another worthwhile new environmental documentary is Living Downstream, in which Dr. Steingrabber examines how location can influence which environmental toxins we experience in our lives and how they can trigger cancer.

Thanks so much for the suggestions, Sandy. I haven’t seen any of those yet, and will definitely check them out.

There are so many well-done documentaries out now. I just love it when people are passionate about things like the environment, food supplies and health issues, and decide to take a stand. The result is some amazing filmmaking by people who are making a difference and alerting us to things we’d otherwise never know about.

Thanks for this list, Jane. I really do like documentaries and have Food, Inc. sitting on my shelf – but have not had a chance to watch it yet. This reminds me I must make the time for this important movie.